1. Field of the Invention
The present invention relates to devices and methods for loading a prosthesis onto a delivery system and, particularly, to devices and methods for loading a valve prosthesis onto a minimally invasive delivery system, for example, a delivery catheter.
2. Background
The replacement of a deficient cardiac valve is often performed by opening a patient's thorax, placing the patient under extracorporeal circulation or peripheral aorto-venous heart assistance, temporarily stopping the heart, surgically opening the heart, excising the deficient valve, and then implanting a prosthetic valve in its place. This procedure has the disadvantage of requiring prolonged patient hospitalization, as well as extensive and often painful recovery. It also presents advanced complexities and significant costs.
To address the risks associated with open-heart implantation, minimally invasive approaches have been developed to facilitate catheter-based implantation of valve prostheses in the heart, including a beating heart. For example, a valve prosthesis formed by attaching a valve to a frame made of a wire or a network of wires has been proposed. Such a valve prosthesis can be contracted radially to introduce the valve prosthesis into the body of the patient percutaneously through a catheter.
To prepare such a valve prosthesis for implantation, the valve prosthesis can be initially provided in an expanded or uncrimped condition, then crimped or compressed around the distal tip of the catheter assembly until the valve prosthesis is as close to or smaller than the diameter of the distal tip as possible. Various methods and devices are available for crimping the valve prosthesis onto the catheter's distal tip, which may include hand-held devices or tabletop devices, for example.
Loading a valve prosthesis on the delivery system, however, can be difficult as the valve prosthesis and crimping device must be carefully inserted over the distal tip of the catheter assembly without damaging the valve or frame, including, for example, support arms of the valve prosthesis. Accordingly, a need exists for a device and method of loading prosthesis onto a delivery system, such as a delivery catheter, that reduces the risk of damage to the prosthesis during loading.